000
AXPZ20 KNHC 241559
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAR 24 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
AXIS ALONG 08N84W TO 01N112W TO 05N130W TO 05N140W.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF AXIS W OF 
125W.  ISOLATED MODERATE CONVECTION WITHIN 90 NM S OF AXIS E OF 
90W. 

...DISCUSSION...
WEAKENING UPPER LEVEL TROUGH FROM 32N125W TO 21N140W GIVING WAY 
AND MERGING WITH STRONGER SHORTWAVE APPROACHING NW CORNER OF 
BASIN.  MODEL GUIDANCE VERY AGGRESSIVE WITH NEW TROUGH 
DEVELOPING CUTOFF CYCLONIC VORTEX AT EDGE OF E PAC ALONG 140W.
VORTEX LIKELY TO ENHANCE DEVELOPMENT OF SURFACE LOW PRES AND 
DETERIORATE WEATHER OVER FORECAST WATERS W OF 120W...BUT LIKELY 
BEYOND PRESENT FORECAST PERIOD.  PLENTY OF AVAILABLE TROPICAL 
MOISTURE BEING ADVECTED NE BY INCREASING JET CORE JUST SE OF 
TROUGH AXIS.  ITCZ CONVECTION FLARING UP UNDER MOISTURE SWATH 
W OF 125W.

BROAD MID/UPPER LEVEL RIDGE DOMINATING FEATURE OVER REMAINDER E 
PAC E OF 120W WITH MINOR WEAK TROUGH FLATTENING CREST N OF 20N 
MAKING W WINDS ALMOST ZONAL ACROSS BAJA CALIFORNIA AND NRN 
MEXICO.  VERY DRY AIR MASS UNDER RIDGE S OF 20N E OF 118W DUE TO 
MODERATE TO STRONG SUBSIDENCE.

ELSEWHERE AT THE SURFACE...
HIGH PRES CENTER 1037 MB AT 32N140W WITH RIDGE EXTENDING SE TO 
14N114W.  STRONG TRADEWINDS N OF 10N W OF 120W WITH LARGE LONG 
PERIOD MIXED NW AND NE SWELLS SPREADING AS FAR S AS 07N.  
REINFORCED RIDGE ALSO FORCING STRONG WINDS AGAINST BAJA 
CALIFORNIA COAST WITH SWELLS PRODUCED BY GALE FORCE WINDS JUST 
N OF AREA ENCROACHING INTO E PAC. 

GULFS OF PAPAGAYO AND PANAMA GAP WINDS DIMINISHING QUICKLY AS 
ATLC HIGH PRES DRIFTS FURTHER E.  

$$
WALLY BARNES